Effect of WB on oxidation behavior and microstructure evolution of ZrB2-SiC coating

In this work, different contents (5, 10, 15 mol.%) of WB were introduced into ZrB2-SiC coatings which were fabricated by vacuum plasma spray technique. The oxidation resistant property of the ZrB2-SiC-WB ternary composite coatings was evaluated in static air at 1500 degrees C. The results showed that appropriate amount of WB addition significantly improved the oxidation resistance of ZrB2-SiC coating, as proved by the reduced weight gain and increased thickness of the liquid layer. The influence of WB and its oxidation product WO3 were analyzed based on the microstructure changes and thermodynamic calculations in detail.